Radius-angle former



March 2, 1948. SNEVA RADIUS-ANGLE FORMER Filed Dec. 11, 1945 2 Sheets-Sheet l AWE; W llll illnumllllll INVENTOR. l/VGOZF 5/9 5147 March 2, 1948. s v v 2,43%,373

RADIUS-ANGLE FORMER Fild Dec. 11, 1943 2 Sheets-Sheet 2 PIE|. 4 1'-IL]. B

Patented Mar. 2, 1943 RADIUS-ANGLE FORMER Ing olf Sneva, Bedford,-lnd.,assignor to W. F. Meyers'Company,Bedforhlnd;ac orporation Application December 11, 1943 Serial No 5i3,89(

1 H 1 This invention pertains to as apparatus for dressing grinding wheels, and preferably form- '3 Claims. gel, 51-224) ing tools by precision grinding on a plain surface wheel, to a prescribed radius of curvature, either concave or convex, or to a prescribed angle, and

wherein the apparatus maybe adjusted and .set to successively grind"awheel or tool to different or compound curvatures and angles merging one into the other. T L, 'Y

Heretofore it has been the practice to first form an abrasive grindingwheel about its periphery to the desired curvature orfangle'into which the tool stock is directly fed, resulting inrthe tool being ground to the curvature or .angle previously formed on, the wheel. Severalobjections to this procedure may be noted. In the'ifirst place it requires an additional operation, i. e., the forming of a wheel.f Secondly, the "radius of curvatures are not precision formed, resulting in the requirement that as the tool is' ground the grinding a series of teeth ona milling cutter to a prescribed curvatu're,in'that all teeth are precision ground to not only the same curvature, but to the samelength, wherefore one tooth will not protrude beyond the'oth'ers as is possible through wear ofthe formed wheel as heretofore employed.

j One feature of theinventi'on lies in the grinding ,of a tool bymanipulation thereof with respect curvatures or angles be constantly checked by 'temticles on the wheel which may be harder or pro- .4

truding, to always follow the same path over '30 the ground surface of the tool'during the grinding operation. j

By means of this invention the above noted objections may be eliminated, whereby tools may be ground toprecis'ion by the mere settingigig thereof, which 'not only elir'ninates the prelim; inary operation of f0rulingthe wheeL'but'requires no checking as to curvaturefor angle 'as 'the tool is ground. 'Additiona1ly, the back and forth movement of the (tool with respect'tofa plain grinding surface ofgthe wheel-"eliminates scratch ing or grooving of the 'surface and'edge; since any outstanding abrasive particle on the wheel will not continuously'fo llow the same pathover the ground surface. Thus," once the tool is prop- '45 erly set with respect to the grinding wheeL'the grinding operation results inthetoolbeing finally formed with precision-"to the prescribed curvature or angle without' -checking by the operator to a wheelhaving a .plain grinding surface or edgefas distinguished from. direct application of theftool to a formed grinding wheel. By this invention means is provided for mounting the tool withrespectto a plaingrinding wheel, preferably cupped, such that the tool may be oscillated in engagementtherewithabout a fixed center of oscillation to provide the prescribed radius of curvature, and [maintain such radius to precision as the grinding progresses and during the oscillaq tion of the tool about its fixed center, and where in such fixed center may be shifted to grind a different radius of curvature, either concave or convex, and followed if desired by a precision setting to direct thegrinding of the tool at an angle tangent to a proceeding or subsequently ground radius of curvature. This permits of a tool being precision ground in virtually one operation, but with different setting, to compound curves and angles merging one with the other. v 'In grinding tungsten carbide or similar ma-' terials, specially formed grinding wheels have been developed, such as Crystolon, silicon car'- bide and'diamond impregnated wheels. However, Crystolon and silicon carbide formed grinding wheelsare made soft especially in order to preventjheatingand cracking'of the tungsten carbide while being'ground; Due to the softness of sucha wheel, it will break down rapidly and; therefore, not retain its true form and thereby will not be suitable for sucl'raccurate form grinding'. Furthermoreydiamond wheels are too expensive to be formed into various contours and shapes to grind the. tools. But with the diamond wheel, shaped as herein disclosed, a carbide tipped tool canbe form ground in accordance with this invention about as easily as a high speed steel A further feature of-the invention resides in Y I theme'chanism for setting 'the tool for dressing a being required. -This is particularly *of' value" in '50 grinding wheel relative to a line intersecting the center of rotation thereof for controlling the radius-angle forming of saidwheel. This is accomplished by means of the hereinafter described provision of spaced stop blocks between which a gauge pin associated with a tool support may freely move to different gauged positions for centering the tool relative to the center of rotation for dressing a curve while permitting freedom of movement for dressing an angle tangent to the radius of such curve.

A still further feature of the invention resides in so relating the respective teeth of a milling cutter to the grinding wheel that they Will be ground with varyingdegrees of clearance. Thus, it may beldesir'ableto provide a clearance of three degrees along the side edges of the tooth as compared with a clearance of ten degrees on the forward cutting edge, blending the clearance between the three and ten degree anglesab'out'th'e curved portion. This is accomplished by mounte. in the former at a prescribed tlhree degree), 1

angle with respect to the grinder table; atwhi ch angle the side edges of the teetfiareto b''gr'our id for clearance, and then presenting the teeth to. the grinding wheel and supporting them at the angle t n de e s p p eara t at w i h the lamis F 1 is a p rs e ive were th to rm showinga "preliminary mounting of thewheel r in bs. Fi 21s a p p ct v (13W of t few r w th he toolhqlderi'a id w h tool applied to a 'grindingwheel. "Figi 3is a diar m at cal i u tra io f' r im'ove f of the tool with resp t'to gr ndi wh n. Fig.4 is an enlarged diagra atic "illustration, Showin the r ndingo' a'i ai'' uttinge e- Fi 5 is the ame ia i'F s. 4,'i-11pstrat nejth gr ing of a convex cutting edge. Fig.6 isthe same as F ustra in th 'gr n ire of a le cutting edge. F g-n isanfill rativeelevation f f h r n in whe l witht. nliedthere to. 'Fig. Sis a perspective vi of afinish'ed tool.

4 slide. Thus the slides l1 and 18 provide a corripound slide support, the latter carrying a vertically and upwardly extending post 19.

Slidably mounted upon the post Hi there is a 5 graduated height dial comprising a locking collar 20 and an adjustable collar 2| rotatable in screw threaded association therewith. The locking collar 20 is adapted to be secured in tool-supporting position on said post, and carries a fixed finger 22 extending into indicating position with respect to suitable graduations on the adjustable collar 2|. Carried on said post above the graduated height dial and located thereby as to height by the proper adjustment of the adjustable 99 1a: .zm ft iefe 2? bel 2? s i a for supporting and clamping either the tool'bit 24 to Joe ground or a diamond nib holder 25, supporting the horizontal diamond nib A at one end, and a 'verticaltliafmond nib B at the other end, said dia- 1n nd nibs beng upported thereby when it is r 1 t'oig wheel II, as shown in Fig. 1. Also, asshown in Fig. 1, there is superimposed o'n' said shaftabove'ithe holder 23 a locator gage 2Q carrying an anvil 21. Preferably one side of the post is flattened as indicated in Fig. 3, against wh h th we e 91 bi 2,9 or nib qu 251's ant en the r w l ar ie Qn Qnes e eweb ed t l w a ne t n wmd in e bii' h, W WlSVI Z QW wa e n l n h 'c nnet io t l b new the,tl insa e te 1 u e threaded for adjustment iiitli' depending finger rigid yp anted to sw n upward y i 'n 'e' e 3 I to eleai'fl'the st Big. 9 is a perspective iew of he"f or merillustrat-.

ing the men-hung of a. milling e t'terther'eon for grinding 'itscutting teeth" a. convex curve. Fig. 1o is'an emer ed. illu'st tiye view of'the relation of the milling cut or Rig. 9, of the grinding wheell Fig; 11 is a scheinatic illustration of the angular relation of'the 'toolsuppo'r'ting post a d h 0 h s wl lb w r n in l Fig. 121's portion ofthe ground. t th or, a nin'g cutterindica'tingby dotted'linsthe varying an of c c'ero nd thr qn i l lc fd ce W H "In the drawings there is illustrated a wheel or tool former adapted to be secured to an adj ustable bed 'plat'e'lfl of a grinder table in adjustable relation to the usual 'n otor driyencuppd grind 5mg wheel u; Theforrner'includes'thebase 12 adapted to be securely'clamped'to the bedp late i0 by any suitablemean s, said baselbeingfpro- Yide' h lqn t d' ne weiedin 'V- mb B n its h tte S ife' rewirin e' qw Pin M for he ,mlrI Qse he ina er d s r ed Sa d base is me ed, i h turn b e q wivel e th he h s? ei dth swivel su rt ii y n n nnu ar .vernier. g le as nd c t d e- M u ited upon e sw ve s i ped .5 there is a primary carriage or elongated slide I! slidab e di m t ic l thempn- Carri d Qn d slide i there i a second r icerria e or tran rse s ide it s idabl PlI Q XQ QIY-Q the leesated transverse slid We re d d wit a a e enga eane h j' T,,epi 1dn"a5 iv tal y "m n e uponithe s1 e i'l'ar 'd' operable by a handle 36; Through s rag d piiii' n said transverse slide may late and locked in adjusted posi tron by 31.? "Said t ansverse slide is provided 7 "outwardly extending pin/5Q moyab t etween a pair of stop blocks 3;.9, e 40 being insertable be; tween'said R41 and vpile (if the stop blocks for positioning the transverseslid' i8 with respect m? 1- Q t the operation, to grind, ml d h t '5001 to b? Fig. 8, wherein a s blended into a con r es clearance, as indi- ZIfq grind to such clear,-

? e he ne i w ee 9 h b d p e adjacent th ding wheel with the y slot 14 to-.

. g whee I len nre q 1 re e the w m v r i n ht r u war ly tew r th whee m xisie he c lla 2' s m nted about .dwar ef the pos th the up er. se ler even with respect to'the x co lar 0 9 a qut /2 nc fo ater. lo in adjustmen diamend ni h lder 2 s a lam d pon the iwld r. 2% sq thatthe horizo a diezn ndnit .19 The hei ht i A is on the diametrieal'center of the-wheel H." The diamond locator gage 26 isthen mounted on the post andthe diamondbrought into contact with anvil 21. Ther'eupon' the nib holder is clamped securely-imposition by the clamping screw 28 and" the locator gage withitsanvil is removed from the post; The height gage in its half inch open position'is clamped tothe' post directly against-the ho1der 23. 1 Theadjustable stop pin 29 is then lowered for engagement with the contact stop pin'30. The wheel 33 is rotated to adjust the elongatedslide until pin 29 engages pin 39, whereupon the dial 34 is set at zero. Thereuponfthe swivel support i is adjusted so that the vernierigraduations thereon and on the base {2 areiset-atzero}. ""In this setting the swivel support is locked'tothe base.

The set screw 3-lon the transverse slide-l8 is then loosened and a selected gage block 49 1s inserted' between 'the pirr 38 and=1one of" the stop blocks 39, thehandle- 36 operating the rack and pinion 35 being -employe'd to slide the pin 38 into contact with menisci; 4H The grinder bed plate is then advanced to bring the diamond nib'A into contact-with the grinding edge of the wheel I I r and is then reciprocated to pass the diamond back and "forth-lightly across the grinding surface'of the wheelior-dressing it. For the grinding of the concavefsurface'ofithe-tool, the cutting edge of the wheel should be dressed down so that the grinding face wi-ll" be-of-less radius than the radius to be ground or in this instance about of an inch with steep angles. With the dial 34 set at zero, the bedplatefeed dial should be read and its reading noted. withthediamond nib A in the dressing position with respect to the wheel.

The cutting edge of the grinding wheelisthereby centered in respect to the axial center of the swivel support.- R fl Thereuponthe-nib holder-=25 is removed andreplaced with the tool bit 24 which preferablyhas had its surface rough ground to approximately the desiredcontoura The height dial should then be set by turning-theadjustable collar 2| on its supporting collar until its scale'reads :3175'of an inch'with the holder 23 loweredto rest thereon;

Thus, the /Z-inch tool-bit is -properly positioned as -to height inespectto the wheel as dressedby I V V t eni s V After th-nibholderhas been replaced with the-tool bit; theelongated slide l-l is retarded until the dial- 34'lreads a-t .125 inch-gplus1030inch,

or the remaining rough stock on'fthe tool bit 24 has its 'extreme-point in contact with the flinch baseoi thewheel. 'The'reupon the elongated slide I1 is securely clamped to the swivel support l5." This adjustment positionsthe top edge of the tool bit 24 at the samerelativelocation as the centered point of thediamond. v

---The set'screw 3l is'loosened and a micrometer applied to the outside of a stop block 39 and pin 38 which are adjusted'to 1.0685 inches. In forming the 4' inch concave radius on the left side ofthe tool bit',-the grinder bed plate [0 is advanced250 inch so-that the left'side line of the tool bit is on the approximate center of'the 5 inch faceof the wheel. The bed plate is locked in this position. This adjustment is important as any error will be'refiected accordingly in the" a The cutting operation is then performed by ad vancing the '-elongatedslide [1 through rotation ofthe wheel 33, whileat the same time manually swivelling theslide about the axial' ce'nt'erof thesupport I5 to swing the tool repeatedly back and forth pastthegrinding edge of the wheel. This is continued until the reading on the dial 34-has advanced from zero to .155 inch,

or until the stop pin 29 engages pin 30, whereupon the prescribed radius of curvature has been reached and the concave curve has been cut to I re-establishes the center of radius for the convex curve. The'reupon the set screw 31 is again tightened. The bed plate In of the grinder table is unlocked andshifted .375 inch, whereupon the reading is carefully noted. It is then shifted an additional .030 inch. This adjustment is necessary to provide a clearance angle forthe stock on the side of the tool bit requiring several cuts to remove. 1 The elongatedslide I1 is then swung to a 90 degrees angle and locked in that position by the locking lever 4| so that the right side of the tool bit 24 faces the wheel. A clearance angle is then formed on the side of the tool bit to about reading of the dial 34. The tool bit is then ground by swinging the swivel support l5 repeatedly back and forth from 90 degrees on one side to 90 degrees on theotherside, or through an arc of 180 degrees" about the grinding surface of the wheel. During this operation the hand wheel 33 is gradually rotated to feed the tool bit into the grinding wheel to the extent of .030 on the dial 34, or until stop pin 29 engages the stop 30. Upon reaching this feed-in point, the convex surface will have been ground to the prescribed radius and blended into the concave radius previously formed.

' The same'procedure may be followed in blending a straight angle surface into one or the other of the curved surfaces by establishing the de-- sired angle through adjustment of the swivelsupport l5 upon the base 12 with the prescribed reading on the dial I'B Locked in place by look; ing lever 42, and with the tool thus positioned at the prescribed angle to the wheel, the bed plate l0 may be reciprocated to move the tool back and lower end of the post 19 there is a fitting 48 for supporting the tooth locating spring finger 49 having its upper end positioned to engage the flat side of a cutting tooth. With the milling cutter thus mounted, each tooth may be indi-' v viduallyground to a prescribed radius in the manner above described with respect to a toolv bit, by first" centering, facing and then swinging the respective teeth about the cutting edge of, the grinding wheel. By reason of'the precision I Qsfififlit v I? I 8 adjustments'abuve eesenisbedieaehteothisiemmd hequahtbaciete it-spesicien a ainst an set by 'otom to.pr ci eiymigesamesadieses lwflm ies. fiQzfifi kl' fi liaise i 4Q Th 1:991; s hs ieb Pi t but to the. sam depths. ,rinx ndimnree iteetdswiw Y almetmn suc teeth in theusnailmanner-bmatermedwheels tek ethe rre iuas c t wher upo he the later eth round will, he lenses thee: he bla k A ma; beriaced nthe othe s de. tee h arlier enoundby ne sonieizthe an on he Qt 3, i, d1e36; manipulated 1n the. vh e This res l sin thetleneet e ppqsi adire tiqn, teier d th QPQQsed. tang nt down and dullin dii oithein i'lt ilfl-illi xfisll l'i teara i-iissur' acerenthe hee i tin l ad, 13.x meeelf-1th r tiger/herein By means of t s;a ran ementiand,thes lee i qr ee n ellhthehe 0, W1 1.- he Qxmedrtm ne 19tqis ly tse ame. ed .1. i, t i ciselythe samerad us q eugva on angle;- t asaid; 111. 6 int i se tmg the center; o rOta: It is preferable th tta e cs e t an or; the tiem eg ind. sves on di enentl-vidirected. radii mil-ling cutter as ground. tr l mi ti l pex n ttinas de itto be manip lated .ed theasso iat da elesitan ent thet t Th nt enclaimedis; I

= LA; g lsienmnaappara us comprising a s Having a swivel support thereon, a registering ca bra ed; ssaiei about. saidsuppqnt and base means onz mk a aid; uppor ta, said. ase n adjusted; position an elongated, slide supported at diustment ii .emeticmalls:v of. sa d. pport, a ad usting; screw, earned: x saidsu port and slide n a; scale; thereon for indicating;- the relaatb along the tti edge tive gositiensi thereb tween a tram,sversev slide by providing a dowei iii u; q sughvqi ggneh 3g; supported: fpriransmfie a i s inent telativet0 t port the ba e mate i edeesee: mal aid; elqneated s ide, m an -liar p sitioning said:

Qt. h cut n edge b te tart g th the; e degs ii: re ree-r liefs e As therein n, heme 4,3 1 a relief of approximately three degre h S d es nd: e t -i eer re ve he i der; tehl grai s, a e e, es mnsversesl de i prescribed: relation thereto,

as. :xture post e tend g, upward y, rom id tnansver e s derahe iit di stment. coll r ad,- ah y seemed to said p st. and. pr v d d h Q ie'he e ht: d ust ent member-ther o a o a. .7 I xtu eeaw ed tolsaidm tad-iustable llQI Q k. iii-' 0.se ze; said tool n he hQrizQntal pla e ia rind ngWheel-i mea swfer s p rti g said a e Qe tetiwe r l tioni e said grin in wheel, he diilstments: to; /s s i s h i perab1 e opxeieetzi h ms n p dete n d. e a iqn to th ma be e d-[i n news. vs de; qt

sim a l mpl ye zln s eQ Erm e th qql iiseliwi i. end m l t l oawmehz pne isat =\e ed andhe 261 hreue e129; e hm t i lar oo-these w the res end neq dies lations. Also, w he th -d m in bs, 1. it ical n f s. l trated n, E

relati e; he eteahouti ma iel center o 9 qrming; appar t s, the comb ne- ..b1 ;-a d wheel pr ov d d swivel support secured alignm nt with; the; c nteneundzbv: said wheelieelon ated slide adiiistabiy -L E IQT dLtQ= slid d mammalian? aidisii nqr ctowardzend away rom. plied 111; the usual; m mento I, sil -said wheel, a transverse slide adjustably asso; Whee to the sit ii orminaeu. e ;0 mete-h i lated h eidn eetedszslidesafixtuxe t e In thus dressing: grindingwheel and'w herete n t a e r di -p iei liew at at dete d r d us. w th the am '9 angles tangent thereto the gange b loe sitioned between. thesga ige in stops 39s to, thereby, set, the n s t a n ini iise ti ei h, s e at rater 129 ion Qfthe Swivel ii mrt i readseiit ndma ene that hee e cetioiieoiseid:

gitudinaily of the elongated slide; I 7 the? 9 positioned and set by said c9;

rsiidah a ad-iustablie on; said,

rt th reon: y, sup:- i adjustable c lar, tqol; hoider: mast-- e. 3: 3 rsi iti-v to? the;

di t k o n e i a ela i e i hfiiaxi'al RZQZMQQEQ'LIQ EI tlnaouetethei L alG1W EE center to the.prescribed,radius-slide v the eomloinaupon, be swiveled as, it is fed; tqrw wheel; provided;

e Wheel to t e r cribedireii si i 'Ijhis swivel action. is;v carried; on V 4 N W V limits gauged y h qale 1 s es ame. rvet ieee p s i y a wheehan-e m a gle tane nt-t ergi' n t U iiswmam aa eislide iiistably; sunn rtedz to; s de d van eXtreme P i i n t and e-3,5 h me nieelly fisa disnmi ewea idiandiaw y m;- e a d to move t e r nsv r ez lid C -fl in ilie ih t verse li e di, 1steb1y au e pin 38 fr n a ement w th-the b ack, cisw th; addens-fated; lide; a fixture ost-s 40 to traverse the intervening spaee tgyvargi the extending upwardly from said transverse; slide, Opposed stop 9 i ms eht q eitu greatness/int, ailment: e ingi pllan-slidehlyi;ad u tab e. n; a d e n ed. he heels H n -A ea 20 i; s tes able: Q iw aidet versed said space, the angle tangpnt t e g p H h unmet se ure :with the; enter:

xia center Q said: SWiVQI- UPDQU, and an for feeding the tool into said whee l while 05011-- e detransyerse sli e a! setting collar extending to selective alignment 5 with the graduations on said adjustable collar for indicating the relative position therebetween for setting the tool relative to the horizontal plane through the axial center of the wheel.

INGOLF SNEVA.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number UNITED STATES PATENTS Name Date Norton Aug. 29, 1893 Goodhew et a1 Nov. 15, 1893 Smith June 11, 1907 Norton Jan. 30, 1923 Hanson Aug. 21, 1923 Weddell June 19, 1928 Dardani Mar. 12, 1935 FOREIGN PATENTS Country Date Switzerland Apr. 1, 1921 

